Re: ext2fs: do directories ever shrink?

Hans Reiser (reiser@idiom.com)
Mon, 13 Jul 1998 16:15:01 -0700


Somebody wrote a Usenix paper based on this idea, and his answer was yes, for
most systems, the directories are small enough that caching all of them is
effective.

Hans

Slyglif Cain wrote:

> > From: alan@lxorguk.ukuu.org.uk (Alan Cox)
> > Date: Mon, 13 Jul 1998 00:39:27 +0100 (BST)
> > Subject: Re: ext2fs: do directories ever shrink?
> >
> > > Maybe on disk. But somehow at up to 50000 files no slowdown is
> > > noticeable when adding or looking up files. This is one of the
> > > areas where I saw big difference in performance between FreeBSD
> > > UFS and Linux ext2fs.
> >
> > Interesting. Is this compared to Linux 2.0 or 2.1 - ie is it smart
> > caching or have they got something clever added on the UFS
> > directory structure we should look at
>
> I realize this has probably been brought up before, but wouldn't it be
> possible to cache the entire directory tree/inode list from a drive?
> Granted, it would take up a large amount of memory, but for systems
> with a lot of memory to spare (96+ MB), it would offer a huge
> performance increase. Also, it would be a good way to use memory over
> 64MB on motherboards which only cache up to 64MB, since even uncached
> memory blows disk away. Perhaps making the amount of memory used by
> this cache configurable at boot time would be helpful as well.
>
> =====================================================================
> // Chris Giard (a.k.a. Slyglif Cain) | I find my life is a lot
> // EMAIL: slyglif@magerealm.com | easier the lower I keep
> // URL: http://www.primenet.com/~slyglif | everyone's expectations.
> // ICQ: 4481627 | --Calvin 1992
>
> -
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.rutgers.edu
> Please read the FAQ at http://www.altern.org/andrebalsa/doc/lkml-faq.html

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.altern.org/andrebalsa/doc/lkml-faq.html